2012年会在什么时候、什么地方、出现什么样的彗星,或者流星之类的小行星说说自己在2012年什么时间、什么地方看到了彗星或流星，越多越好

2012年会在什么时候、什么地方、出现什么样的彗星,或者流星之类的小行星说说自己在2012年什么时间、什么地方看到了彗星或流星，越多越好
2012年会在什么时候、什么地方、出现什么样的彗星,或者流星之类的小行星
说说自己在2012年什么时间、什么地方看到了彗星或流星，越多越好

2012年会在什么时候、什么地方、出现什么样的彗星,或者流星之类的小行星说说自己在2012年什么时间、什么地方看到了彗星或流星，越多越好
December 21st,2008
2012:No Comet
Written by Ian O'Neill
Is a 2012 doomsday comet coming straight at us?
According to 2012 doomsday proponents,something big is out to get us.By "som
ething big" I mean some uncontrollable cosmic entity (i.e.Planet X,Nibiru or
a "killer" solar flare),and by "us" I mean the whole of planet Earth.Pinnin
g 2012 doomsday scenarios on the end of the ancient Mayan "Long Count" calenda
r appears to be growing momentum amongst authors,websites,documentaries and
(my personal favourite) YouTube videos.According to them,something bad is go
ing to happen on or around December 21st 2012.Probably the most interesting d
ifference between the 2012 doomsday scenario and the doomsday prophecies of th
e past is that almost every possible (and impossible鈥 or implausible) harbing
er of doom is being suggested as a planet killer.
So,in this sixth article addressing another astronomical doomsday scenario,I
will look at the theory that there is a comet currently out there in deep spa
ce,slowly making its final approach on its parabolic orbit toward Earth.But
before you get worried,you'll be glad to hear that the 2012 cometary impact t
heory is as watertight as a teabag; there is no object observed out there and
there is certainly no evidence to suggest there could be a comet impact in 201
2鈥 and here's why鈥?br/>Marketing Doomsday
In four years today (December 21st 2012),the world will be coming to an end a
ccording to a few misguided individuals.Doomsayers always begin their argumen
ts using an ancient calendar (plus a heavy dose of Bible Codes,I Ching and an
cient Sumerian cuneiform scriptures) to support their new and inventive way th
e world may end.Alas,most doomsday theories are based on over-hyped scientif
ic misinterpretation and outright lies.Usually there is a book to sell or web
site to promote.After all,there is nothing more profitable than fear.
Interestingly,I started writing for the Universe Today a year ago today,exac
tly five years before the end of the Mayan Long Count calendar.Don't go readi
ng too much into this little fact,pure coincidence,but I think it would be f
itting to write the sixth in my series of 2012 articles exposing the myths sur
rounding this date.
You've probably seen the prolific ads for the "2012 Comet" across a range of w
ebsites,so I decided to delve into this particular theory to see if there is
any truth behind the claims that a comet (or "comet planet") is approaching Ea
rth on a collision course.To cut a long story short,I can categorically say
that no cometary impact is imminent.Any accusations of government cover-ups a
re to hide the poor science doomsayers are citing (much like the Planet X/Nibi
ru connection).If you want the long story,read on鈥?br/>The Comet Threat
Before we look at the claims behind this doomsday scenario,we must first stud
y Earth's risk of actually being hit by a comet.We know we've been hit by com
ets in the past,and we will most definitely be hit by more in the future,but
the coast is clear for at least a few decades from a marauding comet or aster
oid.In fact,meteoroids in the form of chunks of rock are far more numerous t
han icy comets,and we are hit by several sizeable rocky meteoroids throughout
the year (take 2008 TC3,the first predicted meteoroid atmospheric impact,fo
r example).
Although rare,planetary impacts by comets do happen.As Shoemaker-Levy 9 show
ed us in 1994 when 2km-wide fragments of the comet bombarded the Jovian atmosp
here,we mustn't be complacent when considering a large impact event by comets
or asteroids.The dazzling light show by Shoemaker-Levy 9 actually stimulated
efforts to increase sky surveys for a possibly catastrophic impact event.Alt
hough a vast number of near-Earth objects (NEOs) have been identified,a very
small number are considered to be a risk.
The 270 meter-wide asteroid 99942 Apophis caused a stir in 2006 when it became
the highest ranking asteroid on the Torino impact hazard scale.Apophis is no
w expected to glide safely past the Earth in 2029,but depending on the gravit
ational deflection caused by Earth in 2029,Apophis could pass through a gravi
tational "keyhole",creating another impact possibility on April 13th,2036.S
till,the odds are not worth betting on; would you put money on a 1 in 45,000
chance of an Apophis 2036 impact?
There are other lumps of rock out there,but most are benign,and certainly no
t a threat to everyday life in 2012.However,we must be aware that asteroids
are a very real future threat to humanity.As a result of this increased aware
ness,other NEOs have been discovered and tracked.Objects such as 2007 VK184,
a 130 meter-wide asteroid may cause problems in the distant future,but the p
robability of impact is still extremely low.Astronomers from the Catalina Sky
Survey estimate a few possible impact dates for 2007 VK184,but the odds neve
r exceed a 0.037% chance of hitting Earth in the next 100 years.Other asteroi
ds are currently being tracked and they may cause some concern over a century
from now (although none surpass a Torino scale of Level 1,and if they do,all
tend to fall back to the "normal" Level 0).
In short,the skies are clear from any imminent (certainly within the next 4 y
ears) impact from an asteroid.Comets do not feature as a significant risk eit
her.There is no astronomical evidence supporting otherwise.